1. Field of the Invention
The present invention relates to a recording medium, a test apparatus and a diagnostic method. Particularly, the present invention relates to a recording medium on which a program for diagnosing test modules in the test apparatus is recorded, the test apparatus and a diagnostic method. The test apparatus includes a plurality of the test modules that provide test signals to device under tests and a control device that controls the plurality of test modules.
2. Related Art
A test apparatus that tests a DUT (Device Under Test) such as a memory, a logic LSI or a SoC (System on Chip) includes a test module that inputs/outputs a signal to/from the DUT. For example, the test apparatus determines pass/fail of the DUT by providing a test signal in response to a call which instructs to measure the value of a reference parameter of the DUT from the test module, receiving an output signal outputted from an output terminal of the DUT in response to the test signal and comparing the test signal with an expected value.
The test apparatus has a diagnostic function in order to determine pass/fail. The test apparatus also diagnoses whether each test module is abnormal in the process of the diagnosis. In diagnosing the test module, the test apparatus determines whether the measurement result is within a normal value by measuring by a measuring instrument a reference voltage, a reference current and a reference resistance of the target test module, for example. Additionally, in diagnosing the test module, the control device of the test apparatus executes a program to transmit a command through a bus such as a GP-IB to control the measuring instrument.
Meanwhile, when the kind of the measuring instrument provided in the test apparatus is changed, the command transmitted from the control device to the measuring instrument is changed, so that it has been necessary to modify the program corresponding to the change of the command. Additionally, when the kind of the measuring instrument provided in the test apparatus is changed, the bus which connects between the measuring instrument and the control device also could be changed. In this case, it has been necessary to modify the program, too. Accordingly, the designer of the test module should have modified the program to diagnose the test module every time the kind of the measuring instrument provided in the test apparatus is changed.
Thus, the advantage of the present invention is to provide a recording medium, a test apparatus and a diagnostic method which are capable of solving the problem accompanying the conventional art. The above and other advantages can be achieved by combining the features recited in independent claims. Then, dependent claims define further effective specific example of the present invention.